Electric-arc lamp



(No Mel.) 2 Sheets-Sheet 1.

E. THOMSON.

ELECTRIC ARG LAMP.

m9291195. Patented Apr. 22, 1884.'-

(No Model.) 2 Sheets-Sheet 2 E. THOMSON.

ELEGTBIG A110 LAMP.

No. 297,195.v Patented Apr. 22,*1884.'

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ELIHU THOMSON, OF LYN N MASSACHUSETTS, ASSIGNOR TO THE THOMSON- HOUSTON ELECTRIC COMPANY, OF CONNECTICUT.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 297,195, dated April 22, 1884-.

Application filed January 4,1884. (No model.)

i rtl/ whom t may concern:

Be it known that I, ELIHU THOMSON, a citizen of theUnited States, and a resident of Lynn inthe county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Electric-Arc Lamps, of which the following is a specification.

My invention has for its object the production of a simple and effective arc-lamp, in which the proper feed movements of the carbons shall be controlled by the action of aderived-circuit coil or magnet of high resistance Working in opposition to or combination WithV a spring or other suitable retractor.

My :invention relates more especially to means for starting the lamp into action by the provision of a coil or magnet in the carboncircuit, which shall supplement or assist the derived-circuit magnet in bringing the feed or governing mechanism of the lamp into proper operative position at the instant the current is turned on, and shall immediately thereafter be shunted or cut out of circuit and held out, so that the operation of adj Listing and feeding 3 the carbons may proceed under the joint control of the high-resistance magnet and its retractor,\vithout the assistance or intervention of said starting or auxiliary coil in the main circuit with the carbons.

My invention also consists in the combination, with the mechanism of an electric-arc lamp in which feed of the carbons is produced by the increase of magnet-power in a derivedcircuit magnet, of auxiliary releasing devices which, in the retracted position of the magncts armature, will permit'the carbons to run together, means actuated by the first flow of current for adjusting or bringing the mechanism controlled by the derived-circuit magnet into proper feed-regulating position, and suitable cut-out or neutralizing devices,whereby, aftersuch adjustment has been brought about, said means may be rendered inoperative and retained in such condition, so that the operation of the lamp may go on by the controlling action of the derived-circuit magnet only.

My invention consists, further, in certain combinations and details that will be hereinafter described, and then pointed out in the 5o claims.

The auxiliary or starting coil or magnet may act directly upon the armature for the derived-circuit magnet, so as to assist thc latter in drawing the armature from its extreme retracted position, and may be, as I have herein- 5 5 after shown, a separate magnet, or said coil may be Wound upon the same core with the derived-circuit coil. The auxiliary coil, according to the arrangements herein described,

is in a circuit closed bythe contact of the car- 6o bons. It is automatically eut out by a suitable switch device or circuit-controller acted upon when the derived-circuit armature shall have moved the lamp mechanism into normal or feed-regulating position, and the cut-out devices are of such construction that said coil remains cut out despite the movements made by said armature in controlling the carbons,

so that the usual operations may take place under the control of the derived-circuit mag- 7o net Without the intervention of said auxiliary coil. Said cut-out devices may be Worked or brought into action by the movement of the derived-circuit armature, or by any other devices whose movement is so timed or controlled as to 7 5 cut out the coil or magnet or otherwise render it inoperative when, through the assisting action of said coil, the feed-controlling mechanism has been brought to such a point that the proper adjustment and feed of the carbon may 8o be intrusted to the conjoint action of the derived-circuit magnet and its retractor. This point is ordinarily the point at which a feed of the carbons would be permitted if they were l separated and free to move. The auxiliary coil may be kept out of circuit or inoperative by any suitable device, mechanical or magnetic. I have herein shown and claimed a mechanical trip device for this purpose; but other devices may be employed, and I have 9o described and claimed in another application magnetic devices. The feed-regulating mechanism of the lamp herein shown is not only released when the derived-circuit magnet acquires a predetermined strength-owing to increase in the length of arc, and overcomes its retractor, but also when said armature is retracted to its extreme position. The release in the latter position permits the carbons to run together, and thus provides a circuit atico starting whereby the auxiliary coil or other device may be energized. Such release may be eit'ected by any suitable device, but prel erably by an auxiliary stop or detent. The mechanism or the stop as well as the mechanism may be moved in bringing the lamp into operative condition. I have shown both nietheds, but do not limit myseltI in this respect, the essence ot' the invention, so far as this head is concerned, consistingin arranging the parts or providing any suitable means whereby the feed mechanism may be released in the retracted position oi' the derived-circuit armature bei'ore starting ot' the lamp, bringing the mechanism into operative position when the current is turned on, and then leaving the lamp to the sole control ol" the derived-circuit magnet and its retractor.

Having explained the general principles of my invention7 l will proceed to describe some oi" the devices that may be used and some ot' the forms that the apparatus may take in practice.

In the accompanying drawings, Figure l is an elevation ot' a lamp constructed in accordance with my invention. Fig. 2 illustrates a modiilication ot' the magnetic arrangements. Fig. 3 illustrates the position ot' the mechanism when the lamp :is in operation. Fig. t is a modification ot' a switching or circuit-con trolling device. Fig. 5 shows a modification of the releasing devices vl'or the feed mechanism. Figs. (i and T show in detail' approved forms ot' switch-contacts. Fig. S snows a form ot' the lain] i-magnet. Fig. El shows another arrangement and construction et' the switching devices and oi' the detent or releasing devices. Fig. l0 illustrates a modification.

l indicates a coil othigh resistance ina derived circuit around the earbons, and acting by means of a core and armature, B, upon a lever, L, in opposition to a retmeting-spring, S, or other retraetor. rlhese parts are of any desired constructions, and are designed to control the position ot' the carbons in any usual way. rlhe armature may be a perforated armature, and the pole end ol' the core conoidal, as shown, and as described in a patent already issued to me, for the purpose ol' giving a uniform magnetic pull in all positions oi the armature l'or the same strength oi' current. The parts might be otherwise constructed or arranged to give the same result. The above is the preferred construction.

The lever L, through a link, l), or otherwise, gives motion to a feed-controlling mechanism oi' any desired kind-such, i'or instance, as a clamp or clutch properly arranged to raise the carbon when the retractor S prevails, and to permit a release ot' the carbon when, through an increase ot arc length, the coil l receives an increasedproportion ol` the current, and its magnetic eil'ccts consequently prevail over the retractor. l have .herein shown the lever as acting on a clutch or clamp such as is contained in prior patents granted to me, and consisting, briefly, of a clamp or clutch body, C, through which the carbon or carbon-carrier R passes, and a clamping toe or jaw, T, pivoted on the body C, and normally held by a spring, Z, against the carrier or carbon, so as to prevent the same from moving downward through the body (I).

F is the usual releasing-stop, arranged in the path of an arm extending i'rom the toe T, so as to release the latter and permit the carbon to feed when the magnet or coil li is sullt ciently energized, owing to increase in the length ot' arc.

ll is an auxiliary stop arranged in the path ofthe clamp or clutch, to permit a release ol' thc carbon when the arlnature l and lever L are drawn back or retracted to an abnormal extent in the opposite direction by the spring S. rFlic stop ll is placed at such a point that during ordinary or normal movements of L in adjusting the carbons the stop will not strike it; but when the current 'is turned oil' and the retraetor pulls the lever to its extreme position the clamp is released by ll, and remains released, so that at again starting the lamp the earbons will be in contact.

G indicates the auxiliary or starting coil, wound in the present case upon the same core with l, and preferably in the same direction, so as, when current Aflows in it, to assist the coil li in pullingthe lever L down into p roper lposition to start the lamp. The coil G might be on a separate core, as indicated in Fig. 2, and act upon the same armature or another armature connected to L, or other device con* trolling the :leed mechanism.

rlhe combination, with the derivtal'circuit coil, of an auxiliary or starting coil. wound on the same core therewith is claimed in an application for patent iiled by ll. W. Rice and myself as `joint inventors January f3, i, No. 116,300.

rFhe magnet i'ormed by the core ol' coils K and G might obviously be a lnnseshoe-n1ag net, as indicated in Fig. t4. lhe coil (t is in a circuit, o, with the earbons, as indicated, while the derived circuit ol" coil l( is indicated by the numeral 5, which is a circuit around the earbons, as is olwious. The positive and negative conductors et' the main circuit are indicated by X Y.

Coil G may be shunted by a switch or circuit controller, J', ol'any suitable construction, that, when in theposition shown in Fig. 3, completes a shunt oi' low resistance, 7, around said coil. Then the shuntis closed, the coil is ineiileetiveais is obvious. Its circuits may be con` trolled in any other desired manner torender it inoperative or inei't'ective. Ma n y suchways will readily occur to electricians, and need not be set out in detail. Switch J' is in Fig. l actuated or controlled by two lugs or projections, M, on the link l) or other portion oi' the devices moving with L, the upper ot' which projections is suitably placed to throw T into the position shown in Fig. 3 when the linl; moves downward from its extreme retracted position under the inl'luence oi" the auxiliary coil G. The lever .l is held in such position by the action ot' the spring N bear- IOO ing endwise against an arm of J and in line with its fulcrum, so that it may act in angle upon the arm and hold J Aeither in the position shown in Fig. 3 or in that shown in Fig. 1. The upper lug, WI, is placed so as to cause the contacts Q to close and shunt coil G at or near the time when, in the downward movement of the clutch, the toeT impinges against the stop F and is released from the rod R. Vhen this occurs the core of G and K de creases in magneticstrength, and the retractor S then acts and raises the clutch, so as to separate the carbons and form the arc, the amount of separation depending in the adjustment of the parts, and the upward movement continuing until there is a balance between the effects of coil Ii and of the spring or retractor S. Thestop H is placed abovethenpward range of the clutch in the ordinary carbon adjusting and feeding movement, and, as already eX- plained, only comes into play on an eXtreme movement of the lever L under the influence of its retractor. Thelower lug or projection, M, is placed at such point that it will only act on the switch J to throw it to the position shown in Fig. 1 -when the lever L is retracted to an extreme position. In moving to such position, which is the position shown in Fig.

1, the lower lug, M, strikes the lever or switch and carries it upward, the spring N acting to throw the contacts Q wide open when the arm aga-inst which the spring acts passes the hori- Zontal, and to afterward hold them open until the coil G again acts. The spring N acts in the same manner to throw and hold the lever on downward movement of L at starting the lam p. Fig. 1 shows the position of the parts when the lamp is out of action and no current is passing. The contacts Q are open, the clutch released by stop H, and the carbons in contact. Then current is turned on, the coil G acts strongly upon the core and pulls down lever L until the clutch is brought to the ordinary or feed-regulating position or plane, and when the stop F is reached the circuit-controller J is operated and the.coil G is cut out, remaining out until the lever is drawn back to its eXtreme position. The carbons are now left to the sole control of the coil K, and the adjustment Aand feed proceed in the well-known and ordinary manner. i

In Fig. et is shown a modified construction ofthe shunting-switch or trip device J, made with knife-edge bearings, so as to give it increased sensitiveness to the action of the lugs M. The lugs M act on an intermediate piece, J held between a spring, N, and an arm projecting from J. The spring N acts, as in Fig. l, to throw the lever J when its arm passes the horizontal line, and. to hold it in either of its two positions, with the contacts Q open or closed. In the arrangement shown in Fig. 5 stationary stop H is replaced by a stop-lever, H H', actuated by the lever L throughA a link, Z, in such manner as to release the jaw T of the clutch upon a determinate upward Amovement of L. This is effected by giving to the releasing end of H a greater movement than that given to the clutch with a given traverse of L. The construction by which this is effected is obvious from an inspection of the figure.

The contacts Q are preferably rubbing contacts, and are best made double or treble. In Figs. 6 and 7 they are shown slit and made in two parts, c b, which do not make contact simultaneously. By such constructionl they are kept effective and always secure a good connection, since whatever spa-rk is formed occurs at b, while c remains always in good order. b is the rst to make and last to break.

Instead of a spring or mechanical device for keeping the circuit-controller or switch closed while the lamp is in action, I may employ a magnetic device such as shown in Fig. 9. This device and equivalent devices embodying an electro-magnet for acting on the switch to keep the starting-circuit through the coil in the carbon-circuit closed are described and specifically claimed in my application for patent filed January 4, 1884, No. 116,406. This figure also shows an arrangement whereby the stop H may be kept out of range ofthe clutch during the operations of the mechanism in feeding and adjusting the carbons. In this case I place an electro-magnet, R2, of low resistance in the shunt closed by the switch J. This magnet acts on an armature carried by J, and holds the contacts Q together. The switchis primarily operated, as in Fig. 1, by the movement of the lever L, under the iniiuence of coil G, from its extreme retracted position. A projection, M, on the lever L raises the le- Ver J, and the magnet R2 holds the lever,after contact is established at Q', until current is withdrawn from the lamp or ceases to iiow through the carbons, whereupon the lever J drops back and opens the shunt, ready for the next opera-tion. The lever J also controls the position of the stop H, and, by raising the same when the contacts Q are closed, removes said stop out of the ordinary range of the clutch in controlling the feed, so that said stop can not release the clutch. After the lamp ceases to operate, the stop is lowered, and is in position to release the clutch on retraction of the armature.

'Instead of employing the magnetic effects of the current in the sta-rting-circuit, I may make use of other electromotor effects, and may therefore use the heat developed by the current in the starting-circuit through any thermostatic arrangement to move the lever L. Such an arrangement is illustrated in Fig. 10, where the coil G is a resistance-coil placed in a cylinder containing a gas or liquid expansible by heat, and acting through a piston to impart movement to the lever. The circuit of the coil may be the same and be controlled upon the same, principle as those of coil G in other gures.

"What I claim as my invention is 1. Th eeombination, in an electric-arc lamp, of a derived-circuit coil or magnet of highresistance, feed-regulatin g mechanism controlled IOO IIO'

thereby, and released upon an extreme re* verse movement of the magnet core or armature, as well as upon a forward movement thereofin the normal operation oi` the lamp, and means for assisting the derived-circuit magnet in bringing the feed mechanism into normal operating position, as and for the purpose described.

2. rllhe combination, in an electriearc lamp, of a feed mechanism and derived-circuit magnet controlling the same, a starting or assisting coil in the circuit with the carbons, and means for rendering said coil inactive and holding it out ot' action while the earbons are burning, as and for the purpose described.

The combination, in an electric-arc lamp, ot' a starting-coil in the circuit through the carbons, releasing devices to permit the carbon to descend freely when the lamp is out of action, and a switch or circuit-controller for rendering the starting-coil inactive as soon as the lamp begins to burn, as and for the purpose described.

4f. In an electric-arc lamp, the combination, with the feed mechanism, of means for permitting a release of the carbon both when the feed-controlling armature is attracted and when it is retracted, as and for the purpose described.

5. In an electric-arc lamp,'the combination ol" a derived-circuit magnet ol" high resistance around the carbons, a starting coil or magnet in circuit with the earbons when the lamp is out of action, and a switch or circuit-controller for shnnting said coil when the lamp is started and holding it cut ont so long as the lamp shall continue in operation.

6. In an electriclamp, the combination, with a derived-circuit magnet and feed-regulating mechanism released to produce a feed when the magnets strength increases with an increase of are, ol` auxiliary releasing devices which permit the carbon to feed when the magnet is de-energized, devices for bringing the feed inechanism at starting into normal or operating position to lift the carbon and form the arc, and means for throwing said dcvices out oi'opcration, whereby the feed mechanism may be left to the control ofthe hi ghresistance derived-circuit magnet.

7. The combination, in an electric lamp whose carbons are normally or at the start in contact, ofv a derived-circuit magnet of high resistance in a branch around the carbons, feed mechanism controlled thereby, a starting coil or magnet in circuit with the carbons, to assist the derived-circuit magnet in start-ing the lamp, and a switch or circuitcontroller for shunting said coil and holding it shunted, so that the lamp may operate runder the control. of the derivedscircuit magnet independently of said coil.

8. The combination, substantially as described, of a derived-circuit magnet, a feed mechanism having an auxiliary stop or detent l'or permitting the carbons to come together when the magnet-armature is abnormally rctracted, as well as when it is drawn forward by the increase of current in the derived-circuit magnet, a coil or magnet in circuit with the carbons for assisting the derived-circuit magnet, and means for shunting said coil when the feed mechanism has been moved to a predetermined point.

9. In an eleetricarc lamp whose mechanism is controlled by a derived-circuit magnet only in the feed-controlling operation, the combination of a startingcircuit, a circuit closer or controller actuated by the 1naguetarmature in its movement to extreme position ,and a spring bearing on said circuit-closer, so as to act upon it at an angle in either of its positions, and to thus hold the contacts open or closed independently ol' the lever when moving in a limited range.

10. The combination, in an electric lamp, ol" a derived-cireuit magnet, a clamp or clutch controlled thereby, stops or detents for releas ing the clutch at either extreme of movement, a coil or magnet for assisting the derived circuit-magnet at starting, and means for automatically preventing an operative llow ofcurrent in said coil when the derived-circuit-magnet armature has been moved to a predetermined point.

l1. rllhe combination, in an electric lamp, of a derived-circuit magnet whose coil is iu a branch of high resistance around the carbons, a starting-coil wound on the same core with said derived-circuit coil and in circuit with the carbons, and a switch or circuit-controller for controlling or cutting off the `flow of current in said latter coils, whereby, after the lamp is started ,it may be left to burn under the sole control of the derived-circuit coil.

' 11.2. The combination, in an electric lamp, ol a clamp or clutch and two releasing-stops for th e latter, arranged in the manner described, to release the carbon or carbon-carrier in either of the cxtreme positions of the clutch.

13. rlhe combination, in an elect-ric lamp, ol" the clamp or clutch having the clamping toe or jaw T and two stops, arranged in the manner described, to release the toe on an upward or downward movement ofthe clutch to a determinate extent.

14. The combination, in an electric lamp, of a high-resistance derivedcircnit iced-regulating magnet, an auxiliary coil in circuit with the carbons for moving the feed-regulating mechanism to a point from which, when retracted, it may raise the upper carbon, and means for automatically shunting said coil and holding it shunted, so that the operations ol" forming the arc and controlling the feed may progress under the control ot' the derivedcii" cuit magnet only.

Signed at Lynn, in the county of Essex and State of Massachusetts, this 21st day ol l)e cember, A. D. 1883.

Illyllill IPUDDISON.

\Vitnesses:

E. VILBUR Rien, Hinnv Rooi-ms. 

